The StopBadware project teamed up with Google, Facebook, Twitter and other major Web content providers on Thursday to create an information-sharing group that aims to hinder attackers’ attempts to spread malware and sell fraudulent goods through online advertisements.

The group, which is called the Ads Integrity Alliance and also includes AOL.com and the Interactive Advertising Bureau among its founders, will allow members to share information on the latest types of attacks and fraud as well as best practices for defeating attackers.

The security problem posed by advertisements is not easy to solve, but the alliance should be able to help companies focus on the best methods to defeat criminals and fraudsters, says Max Weinstein, executive director of StopBadware.

“It’s about managing the problem effectively,” he says. “It is super-important that ads that are carrying malware and these other types of bad ads are cut off by the companies that are carrying the ads before they get to the user’s desktop.”

Online advertisements propagating malware, known as “malvertisments,” are one of the hardest threats to detect, because the malicious ad may only appear occasionally on any particular site. More than six out of every 10 sites hosting malware are not fake fronts on the Web, but legitimate sites that have been compromised or hosting malvertisements, according to Symantec’s Norton Safe Web service. And it’s not just risky sites—such as porn and gambling sites—that host the most malware, but religious sites.

In 2011, for example, Google disabled some 130 million ads and banned more than 800,000 advertisers for violating its policies, a fivefold increase over three years.

“No individual business or law-enforcement agency can single-handedly eliminate these bad actors from the entire Web,” the company stated in a blog post. “The best way to tackle common problems across a highly interconnected Web, and to move the whole Web forward, is for the industry to work together, build best practices and systems, and make information-sharing simple.”

The Ads Integrity Alliance will share information about bad advertisements, create best practices to stop malvertising, and work to inform consumers and policy makers about the threat, Weinstein says. The creation of the group parallels that in other industries, where small information-sharing groups have come together to protect against attackers impacting their businesses.